Scotland Yard detectives are investigating claims that a Times journalist, named as Patrick Foster, accessed the email of Lancashire detective Richard Horton in 2009 to unmask him as the author of the anonymous NightJack blog.

Harding told the inquiry on 17 January that one of his reporters was issued with a formal written warning for professional misconduct for gaining unauthorised access to an email account.

The editor provided Lord Justice Leveson with further evidence about the incident in a letter made public on 25 January.

The inquiry has heard that The Times fought a High Court battle to name Mr Horton as the writer of the NightJack blog after the reporter told his managers he had tried to access an email account.

Sun editor Dominic Mohan, who told the inquiry last month that his paper could be a “powerful force for good”, has also been recalled to answer further questions next week.

Four current and former senior Sun journalists were arrested along with a serving Metropolitan Police officer over alleged police bribes at the weekend. All five men have been bailed.

It is understood that Deputy Assistant Commissioner Sue Akers, the head of Scotland Yard’s phone hacking investigation team, and Daily Mail editor Paul Dacre will give evidence to Lord Justice Leveson on Monday.